Given the band's reputation for sprawling, quasi-freeform live shows, it only makes sense that the first documentary devoted to a comprehensive history of the Grateful Dead should span four hours — and offer an eclectic, impressionistic overview of the group as well as the lives its members led behind the scenes.

Long Strange Trip, helmed by acclaimed director Amir-Bar Lev (My Kid Could Paint That, The Tillman Story), brings the Dead's singular tale to select theaters for a limited run on May 26, with streaming set to begin exclusively on Amazon Prime starting June 2. As surviving members Mickey Hart and Bob Weir told Rolling Stone in comments collected for an overview of the movie, fans can expect a viewing experience that — like the music that inspired it — covers an impressive amount of territory.

"It's charming and it's heartfelt," Hart reflected of the film. "But it's sad in some ways. It's not a date movie. I wouldn't take my wife to see it."

The sadness Hart references relates in part to the struggles faced — and ultimately succumbed to — by frontman Jerry Garcia, whose conflicted relationship with the Dead's enduring fame is offered an honest appraisal during the film's four-hour runtime. Hart, describing the last years of Garcia's life as "kind of tragic," added that the footage "shows you how lonely it is when people want to pick you apart and give you no peace just because they love you to death."

All of which is not to say viewers should brace themselves for an unbearably sad experience. Comparing his own creative process with Long Strange Trip to the Dead's, Lev told Rolling Stone he opened himself up to "improvise and go where it took us," and the result is a movie that earned critical praise at Sundance and has already been described as a documentary you don't need to love the Dead to enjoy — in spite of its imposing length. Without sugarcoating the pain in parts of their story, Weir argued that it's "counterbalanced by the music itself" and added, "A lot of the stories in the film are fairly dark, but there's a light that shines above all of that."

As previously reported, Long Strange Trip's arrival roughly coincides with the return of 1977's The Grateful Dead Movie to theaters, where it's scheduled to screen for one night only on April 20 — including a sneak peek at the new documentary. Check Fathom Events' website for screenings in your area.